[v4 PATCH 05/12] spi/atmel_spi: update the dt support

Wenyou Yang
2013-01-14T07:34:30Z

To meet the different spi IP version of atmel SoC,
add the more compatible with different config and devtype.

The "has_dma_support" is used to select the dma engine transfer mode.

The "has_wdrbt" indicate if there is the "WDRBT" bit in the Mode Register,
WDRBT (Wait Data Read Before Transfer),if WDRBT is set,
a transfer can start only if the Receive Data Register is empty,i.e. does not
contain any unread data, to prevent overrun error in reception

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
---
drivers/spi/spi-atmel.c | 134 ++++++++++++++++++++++++++++++++++++++++-------
1 file changed, 115 insertions(+), 19 deletions(-)

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 8f6f0a0..43c1f63 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -71,6 +71,8 @@
#define SPI_FDIV_SIZE 1
#define SPI_MODFDIS_OFFSET 4
#define SPI_MODFDIS_SIZE 1
+#define SPI_WDRBT_OFFSET 5
+#define SPI_WDRBT_SIZE 1
#define SPI_LLB_OFFSET 7
#define SPI_LLB_SIZE 1
#define SPI_PCS_OFFSET 16
@@ -186,6 +188,12 @@
* DMA transfers; transfer queue progress is driven by IRQs. The clock
* framework provides the base clock, subdivided for each spi_device.
*/
+struct atmel_spi_pdata {
+ u8 version;
+ bool has_dma_support;
+ bool has_wdrbt;
+};
+
struct atmel_spi {
spinlock_t lock;
unsigned long flags;
@@ -204,6 +212,7 @@ struct atmel_spi {
struct spi_transfer *next_transfer;
unsigned long next_remaining_bytes;
int done_status;
+ struct atmel_spi_pdata *pdata;

void *buffer;
dma_addr_t buffer_dma;
@@ -218,6 +227,69 @@ struct atmel_spi_device {
#define BUFFER_SIZE PAGE_SIZE
#define INVALID_DMA_ADDRESS 0xffffffff

+static struct atmel_spi_pdata at91rm9200_config = {
+ .version = 1,
+ .has_dma_support = false,
+ .has_wdrbt = false,
+};
+
+static struct atmel_spi_pdata at91sam9260_config = {
+ .version = 2,
+ .has_dma_support = false,
+ .has_wdrbt = false,
+};
+
+static struct atmel_spi_pdata at91sam9g45_config = {
+ .version = 2,
+ .has_dma_support = false,
+ .has_wdrbt = true,
+};
+
+static struct atmel_spi_pdata at91sam9x5_config = {
+ .version = 2,
+ .has_dma_support = true,
+ .has_wdrbt = true,
+};
+
+static const struct platform_device_id atmel_spi_devtypes[] = {
+ {
+ .name = "spi-at91rm9200",
+ .driver_data = (unsigned long) &at91rm9200_config,
+ }, {
+ .name = "spi-at91sam9260",
+ .driver_data = (unsigned long) &at91sam9260_config,
+ }, {
+ .name = "spi-at91sam9g45",
+ .driver_data = (unsigned long) &at91sam9g45_config,
+ }, {
+ .name = "spi-at91sam9x5",
+ .driver_data = (unsigned long) &at91sam9x5_config,
+ }, {
+ /* sentinel */
+ }
+};
+
+#if defined(CONFIG_OF)
+static const struct of_device_id atmel_spi_dt_ids[] = {
+ {
+ .compatible = "atmel,at91rm9200-spi",
+ .data = &at91rm9200_config,
+ } , {
+ .compatible = "atmel,at91sam9260-spi",
+ .data = &at91sam9260_config,
+ } , {
+ .compatible = "atmel,at91sam9g45-spi",
+ .data = &at91sam9g45_config,
+ } , {
+ .compatible = "atmel,at91sam9x5-spi",
+ .data = &at91sam9x5_config,
+ }, {
+ /* sentinel */
+ }
+};
+MODULE_DEVICE_TABLE(of, atmel_spi_dt_ids);
+#endif
+
/*
* Version 2 of the SPI controller has
* - CR.LASTXFER
@@ -230,11 +302,12 @@ struct atmel_spi_device {
* register, but I haven't checked that it exists on all chips, and
* this is cheaper anyway.
*/
-static bool atmel_spi_is_v2(void)
+static bool atmel_spi_is_v2(struct atmel_spi *as)
{
- return !cpu_is_at91rm9200();
+ return as->pdata->version == 2;
}

+
/*
* Earlier SPI controllers (e.g. on at91rm9200) have a design bug whereby
* they assume that spi slave device state will not change on deselect, so
@@ -266,15 +339,21 @@ static void cs_activate(struct atmel_spi *as, struct spi_device *spi)
unsigned active = spi->mode & SPI_CS_HIGH;
u32 mr;

- if (atmel_spi_is_v2()) {
+ if (atmel_spi_is_v2(as)) {
/*
* Always use CSR0. This ensures that the clock
* switches to the correct idle polarity before we
* toggle the CS.
*/
spi_writel(as, CSR0, asd->csr);
- spi_writel(as, MR, SPI_BF(PCS, 0x0e) | SPI_BIT(MODFDIS)
- | SPI_BIT(MSTR));
+
+ if (as->pdata->has_wdrbt)
+ spi_writel(as, MR, SPI_BF(PCS, 0x0e) | SPI_BIT(MSTR)
+ | SPI_BIT(MODFDIS) | SPI_BIT(WDRBT));
+ else
+ spi_writel(as, MR, SPI_BF(PCS, 0x0e)
+ | SPI_BIT(MSTR) | SPI_BIT(MODFDIS));
+
mr = spi_readl(as, MR);
gpio_set_value(asd->npcs_pin, active);
} else {
@@ -321,7 +400,7 @@ static void cs_deactivate(struct atmel_spi *as, struct spi_device *spi)
asd->npcs_pin, active ? " (low)" : "",
mr);

- if (atmel_spi_is_v2() || spi->chip_select != 0)
+ if (atmel_spi_is_v2(as) || spi->chip_select != 0)
gpio_set_value(asd->npcs_pin, !active);
}

@@ -734,7 +813,7 @@ static int atmel_spi_setup(struct spi_device *spi)
}

/* see notes above re chipselect */
- if (!atmel_spi_is_v2()
+ if (!atmel_spi_is_v2(as)
&& spi->chip_select == 0
&& (spi->mode & SPI_CS_HIGH)) {
dev_dbg(&spi->dev, "setup: can't be active-high\n");
@@ -743,7 +822,7 @@ static int atmel_spi_setup(struct spi_device *spi)

/* v1 chips start out at half the peripheral bus speed. */
bus_hz = clk_get_rate(as->clk);
- if (!atmel_spi_is_v2())
+ if (!atmel_spi_is_v2(as))
bus_hz /= 2;

if (spi->max_speed_hz) {
@@ -817,7 +896,7 @@ static int atmel_spi_setup(struct spi_device *spi)
"setup: %lu Hz bpw %u mode 0x%x -> csr%d %08x\n",
bus_hz / scbr, bits, spi->mode, spi->chip_select, csr);

- if (!atmel_spi_is_v2())
+ if (!atmel_spi_is_v2(as))
spi_writel(as, CSR0 + 4 * spi->chip_select, csr);

return 0;
@@ -921,6 +1000,21 @@ static void atmel_spi_cleanup(struct spi_device *spi)
kfree(asd);
}

+static struct atmel_spi_pdata * __devinit atmel_spi_get_driver_data(
+ struct platform_device *pdev)
+{
+ if (pdev->dev.of_node) {
+ const struct of_device_id *match;
+ match = of_match_node(atmel_spi_dt_ids, pdev->dev.of_node);
+ if (!match)
+ return NULL;
+ return (struct atmel_spi_pdata *) match->data;
+ }
+
+ return (struct atmel_spi_pdata *)
+ platform_get_device_id(pdev)->driver_data;
+}
+
/*-------------------------------------------------------------------------*/

static int atmel_spi_probe(struct platform_device *pdev)
@@ -987,11 +1081,21 @@ static int atmel_spi_probe(struct platform_device *pdev)
if (ret)
goto out_unmap_regs;

+ as->pdata = atmel_spi_get_driver_data(pdev);
+ if (!as->pdata)
+ goto out_unmap_regs;
+
/* Initialize the hardware */
clk_enable(clk);
spi_writel(as, CR, SPI_BIT(SWRST));
spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */
- spi_writel(as, MR, SPI_BIT(MSTR) | SPI_BIT(MODFDIS));
+
+ if (as->pdata->has_wdrbt)
+ spi_writel(as, MR,
+ SPI_BIT(MSTR) | SPI_BIT(MODFDIS) | SPI_BIT(WDRBT));
+ else
+ spi_writel(as, MR, SPI_BIT(MSTR) | SPI_BIT(MODFDIS));
+
spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS));
spi_writel(as, CR, SPI_BIT(SPIEN));

@@ -1084,21 +1188,13 @@ static int atmel_spi_resume(struct platform_device *pdev)
#define atmel_spi_resume NULL
#endif

-#if defined(CONFIG_OF)
-static const struct of_device_id atmel_spi_dt_ids[] = {
- { .compatible = "atmel,at91rm9200-spi" },
- { /* sentinel */ }
-};
-
-MODULE_DEVICE_TABLE(of, atmel_spi_dt_ids);
-#endif
-
static struct platform_driver atmel_spi_driver = {
.driver = {
.name = "atmel_spi",
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(atmel_spi_dt_ids),
},
+ .id_table = atmel_spi_devtypes,
.suspend = atmel_spi_suspend,
.resume = atmel_spi_resume,
.probe = atmel_spi_probe,
--
1.7.9.5